Lawyers for Britney Spears' conservators have filed an urgent request in a Los Angeles court asking a judge to seal certain records in her ongoing legal case.

The pop superstar's father Jamie was placed in charge of her legal and business affairs in 2008 following the singer's much-publicized breakdown and hospitalization, and her fiance Jason Trawick was made a co-conservator in April.

The move was reportedly part of the process to gradually transfer control of the estate back to Spears.

However, the conservatorship case returned to court on Thursday when it emerged that legal representatives had moved to block particular documents, which have been deemed "highly sensitive", from public view. They allege information in the files could cause "irreparable harm and immediate danger" to Spears if they are not sealed.

Specific information about the papers were unavailable as WENN went to press, but sources tell TMZ.com the records in question detail a mystery medical condition Spears allegedly suffers from which is said to affect her state of mind.